Seniority is a union controlled list
The way I see it, is, "Seniority" is "length of service/DOJ" isn't it, and you can use it to make redundancies, albeit it may have to be part of a matrix of criteria these days, as long as you can also show it is not age discriminatory. It won't be at BA. That said, if you use a matrix its not LIFO.
MartinAir guys have recently been stuck on the bottom of the list but they're contesting this because I believe they are claiming the incorporation of MartinAir into KLM is a
merger not a
takeover.